Social change is more likely to occur in societies where there is a mixture of different kinds of people than in societies where people are similar in many ways. The simple reason for this is that there are more different ways of looking at things present in the first kind of society. There are more ideas, more disagreements in interest, and more groups and organizations with different beliefs. In addition, there is usually a greater worldly interest and greater tolerance in mixed societies. All these factors （因素）tend to promote social change by opening more areas of life to decision. In a society where people are similar in many ways, there are fewer situations for people to see the need or the chance for change because everything seems to be the same. And although conditions may not be satisfactory, they are at least customary and clear.
Within a society, social change is also likely to occur more frequently and more readily in the material aspects of the culture than in the non-material aspects, for example, in technology rather than in values; in what has been learned later in life rather than what was learned early; in the simple elements（要素）rather than in the complex ones; and in elements that are acceptable to the culture rather than in strange ones.
Besides, social change is easier if it is gradual. For example, it comes more readily in human relations on a continuous scale rather than one with a sharp division. This is one reason why change has not come more quickly to Black Americans as compared to other American minorities, because of the sharp difference in appearance between them and their white fellows.
The underlined part “greater tolerance” in Paragraph 1 probably refers to “________”.

A．quicker adaptation to changing conditions

B．greater willingness to accept social change

C．more respect for different beliefs and behavior

D．greater readiness to agree to different conditions

Why is social change less likely to occur in a society where people are similar in many ways?

A．They are so conservative that they tend to slow down social change.

B．They can easily get what they want in the material aspect of society.

C．They are so used to their conditions that they seldom want to change.

D．They have similar needs that can be satisfied without much difficulty.

Which of the following factors probably tends to promote social change fast?

A．Different points of view.

B．Traditional values.

C．Sharp divisions in relations.

D．Similar appearances.

What is this passage mainly discussing?

A．Two different kinds of society.

B．Consequences of social change.

C．The importance of social change.

D．Certain factors affecting social change.